<div dir="ltr">Hello David,<div><br></div><div>This sounds like something that can be accomplished with protocols and default implementations provided in protocol extensions. If you've watched <a href="https://developer.apple.com/videos/play/wwdc2015-408/">Protocol-Oriented Programming in Swift [Session 408]</a>, slides 168 and on, once he begins talking about Protocol Extensions, is the relevant part. It looks like the functionality that you've described is already present in this feature.</div><div><br></div><div>TJ</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Fri, Dec 4, 2015 at 3:30 AM, David Scrève <span dir="ltr"><<a href="mailto:david.screve@dlta-studio.com" target="_blank">david.screve@dlta-studio.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Hi Everyone,<br>
<br>
Nice to see this new swift-evolution process….I’m not sure to completely understand the whole process of requesting evolutions, but I’m trying<br>
to do…<br>
<br>
As I develop sort of framework, I usually have classes that I wanted to partially in the framework and force the user to implement others parts.<br>
<br>
For example, I have a WebService class that manage the whole process to perform asynchronous call, error management.<br>
This class has an abstract property that is specific for each WebService call.<br>
<br>
Then I would like to make the URL property abstract and, consequently, the whole WebService class abstract : The WebService cannot be directly instantiated.<br>
<br>
The goal of this feature would be to extend to method.<br>
This behavior already exists in Java and is really useful.<br>
<br>
The workaround is to make an URL property that returns invalid value or make assertion, but the error is only detected at runtime.<br>
<br>
My proposal would be to just add a keyword before func, class or var. An abstract property or func should not provide implementation.<br>
<br>
Regards,<br>
<br>
<br>
David<br>
<br>
<br>
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<br></blockquote></div><br></div>